Mariner 10February 5, 1974

Artist's concept of Mariner 10 and Venus

Mariner 10 continues on its journey
to be the first craft to encounter two planets at close range. At
its first destination Venus, the spacecraft produces the first clear pictures of the Venusian
chevron clouds and performs other atmospheric studies.

Then, using the gravity of Venus to bend
its flight path, Mariner sets a course for Mercury.